Study On Mechanical Response Of Ferromagnetic Materials Under Multi-physics Coupling Condition

Ferromagnetic material is widely used in daily life and industrial are as an important functional material,its production and application are inextricably linked with its mechanical and magnetic properties.With the continuous progress of science and technology,more and more ferromagnetic materials are served in the high temperature,complex mechanical load environment,obviously the traditional test means have been unable to meet the test requirements of ferromagnetic materials which are served in complex environment.Therefore,developing the instrument which can effectively measure the magneto-magnetic response of the ferromagnetic material under the multi-field coupling,and researching the performance of the ferromagnetic material,will provide the foundation and support to the research and development of the ferromagnetic material,performance analysis and the reliability evaluation,it will not only promote the continuous development of materials science,but also is expected to produce significant economic benefits.In this paper,the present situation of material performance testing theory and technology of multi-physics field coupling was reviewed,and the basic theory and technology of ferromagnetic material performance test were introduced in detail.On the basis of this work,the magnetostrictive test module was designed based on the in situ testing instrument for micro mechanical properties of materials,the commercialized test device for hysteresis loop test was updated,in the end,researched the mechanical and magnetic responses of three typical ferromagnetic materials under the coupling of multifield.The research work can be summarized as follows:Based on the theory and technology of multi-physics coupling test,the magnetostrictive property test unit of multi-load and multi-field coupling material micro-mechanical performance test instrument was designed.Using the Workbenchmodule in Ansys,the characteristics of key components and the distribution of temperature and magnetic field in the designed test cell were simulated and analyzed,the performance of strain measurement system and positioning platform was analyzed and analyzed,and the structural rationality of the designed test unit was verified.On this basis,the commercialized test device for hysteresis loop test was updated.The purchased commercial hysteresis loop test device did not have the force detection function,the butterfly spring was added in the device,the pressure of the specimen can be derived by measuring the deformation of the disc spring,and then hysteresis loop can be tested under different pressure.The performance of the device was tested and analyzed,and the accuracy and reproducibility of the test device were verified by the Alnico standard.On the basis of the above work,the paper selected Alnico,ferrite and TBdy Fe as typical research objects,carried out a more systematic study of mechanical and magnetic response under multi-field coupling environment.The magnetostrictive properties of TBdy Fe were studied.It was found that the high temperature effect and the compressive stress perpendicular to the direction of the magnetic field lead to the weakening of the magnetostrictive properties in the different directions of the terbium.In this paper,the experimental study on the performance of Hysteresis loop with multi-physics field coupling of Alnico,ferrite and TBdy Fe was carried out.For the study of alnico,it was found that the increase of pressure leads to the decrease of intrinsic coercivity of Al Ni Co,but has no significant effect on the residual magnetization.The increase of temperature leads to the decrease of intrinsic coercivity and residual magnetization.For the study of ferrite,it was found that the increase of temperature leads to the decrease of residual magnetization and the intrinsic coercivity of ferrite.The effect of pressure on the residual magnetization and intrinsic coercivity has no significant effect.For the study of TBdy Fe,it is found that the maximum magnetization of TBdy Fe is very obvious with the decrease of temperature,and the increase of pressure will decrease the maximum magnetization.